Caring Currents

The HALO, a New Easy Breast Cancer Test, Arrives

Last updated:

July 17, 2009
M&S Cleavage
Image by poolski used under the creative commons attribution share alike license.

A new breast cancer test has arrived, called the HALO test, and it's all over the news. This summer, HALO breast cancer test machines started arriving at clinics and doctor's offices around the country, and ads and articles in local papers are everywhere. But, of course, everyone's wondering: Who should have it and when, and where to get it?

Here's the first thing you need to know: Women may not be offered this test by their doctors, at least at first, as it requires a special machine, and it's not covered by insurance. Instead, in the near future, most women will take the test at specialized clinics and labs and pay the fee (usually between $75 and $150) themselves.

It's also important to understand that unlike diagnostic tools, such as mammograms, ultrasounds, MRIs, and biopsies, the HALO test doesn't screen for breast cancer itself. Instead it evaluates a woman's risk of developing breast cancer in the future. Even if you have the HALO test, it's important to get all your regular exams as well.

How does it work?
Unlike mammograms, which take an image of the breast tissue itself, the Halo breast pap test, as it's officially called, tests the fluid inside the milk ducts, called nipple aspirate fluid (NAF), for abnormal cells. The official term for the condition they're looking for is "atypical ductal hyperplasia."

The machine works like a breast pump, pressurizing the breast and extracting fluid. However, only about 50 percent of women produce fluid in their ducts. If the test doesn't find fluid, the test automatically reports a "negative for breast cancer," since women who don't produce fluid in their breasts are considered low risk. If the ducts do produce fluid, a sample is sent to a lab and results are available in a few days.

Because 90 percent of all breast cancer starts in the milk ducts, the test's designers say testing this fluid can reveal changes that occur as early as five years before an actual breast lump, or tumor, would appear. A positive HALO test result reveals that a woman's risk of developing breast cancer is four to five times higher than average. (A family history of breast cancer merely doubles a woman's risk of the disease, so a quadrupling of risk is a significant increase.) However, only 1 to 2 percent of women who take the HALO test can expect a "positive" reading.

Who should have the HALO test?
This test is most important -- and most effective -- for women between the ages of 25 and 55. After that age, many women stop producing fluid in the milk ducts, but this lack of fluid doesn't tell the whole story. Also, mammograms become more effective after age 55, so they're a better tool for older women. Since annual mammograms are only recommended for women ages 40 and over, this test will be extremely important for women not yet having annual mammograms.

However, experts haven't yet said whether women over age 55 should skip the HALO test, because if a woman is still producing fluid, the test could be an effective indicator. A conservative approach would say it's worthwhile for older women to take the test once, and if they do have fluid, to keep taking it until they don't. Also, older women with dense breasts might want to consider the HALO test as an additional screening tool.

Is it accurate?
The jury is still deep in deliberation on this one. The test's manufacturers won FDA approval, but many experts say there's simply not enough data yet to know how accurate the test will prove over time. The concern is that a woman who got a negative HALO test result might consider herself not at risk -- and not have the other tests she should have. However, if you view it as simply another tool and continue to do all your other medical tests as necessary, it can't hurt.